CVE-2026-12221 (GCVE-0-2026-12221)
Vulnerability from cvelistv5 – Published: 2026-06-15 05:00 – Updated: 2026-06-27 05:45
VLAI
EPSS
VEX
Title
Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflow
Summary
A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure and is working on a patch to fix it.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-15 12:50 UTC
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://vuldb.com/vuln/370864 | vdb-entrytechnical-description |
| https://vuldb.com/vuln/370864/cti | signaturepermissions-required |
| https://vuldb.com/cve/CVE-2026-12221 | third-party-advisory |
| https://vuldb.com/submit/834207 | third-party-advisory |
| http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrad… | broken-linkexploitpatch |
Impacted products
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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